Which Religion Will “Win”?

Alan Wolfe writes about worldwide religious market share in the March issue of The Atlantic:

Hindus and Buddhists together make up 20 percent of the world’s people, and high birthrates in the countries in which they are dominant suggest that this proportion will grow.

There’s not much more on Buddhism, but there is an interesting graphic plotting countries relative to wealth (the x-axis) and religiosity (y). As usual, much of the preoccupation of the article is with the rapid growth of Islam and the United States’ atypical religiosity compared to western Europe. Does secularism grow as wealth increases? It doesn’t seem to in this country, anyway.